A report in the recent literature has described the antipsychotic, antidepressant and sedative activities of compounds known as hexahydro-benzo[d]naphtho[2,1-b]azepines (European Patent Application No. 230270). These compounds include [-]trans 6,7,7a,8,9,13b-hexahydro-3-chloro-2-hydroxy-N-methyl-5H-benzo[d]naphtho-[2 ,1-b]-azepine.
Other antipsychotic drugs such as R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7-ol have been shown to be selective binders of dopamine D-1 receptors (J. Pharmacol. Exp. Ther., 226: 462 (1983)). This selectivity is reported to be 2500 fold or virtually to the exclusion of the dopamine D-2 receptors. Such specificity indicates that the compound may possess unusual antipsychotic effects and low liability for producing side effects such as extrapyramidal effects in humans. This is so because D-1 receptor antagonism like D-2 receptor antagonism is associated with antipsychotic effects in laboratory animal models but D-2 receptor antagonism is also associated with the untoward side-effects characteristic of most known neuroleptics (e.g., hyperprolactinemia in animals and humans).
Tritiated R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7-ol has also been used in a method of determining the level of D-1 antagonism of a neuroleptic drug. See U.S. Pat. No. 4,760,029.